blob: 9835312d5a91e398791d36bc0ea83b0cb22318ad [file] [log] [blame]
Chris Metcalf867e3592010-05-28 23:09:12 -04001/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 *
14 * Copied from i386: Ross Biro 1/23/92
15 */
16
17#include <linux/kernel.h>
18#include <linux/ptrace.h>
19#include <linux/kprobes.h>
20#include <linux/compat.h>
21#include <linux/uaccess.h>
Simon Marchi7be68282012-12-17 20:08:09 -050022#include <linux/regset.h>
23#include <linux/elf.h>
Chris Metcalf0707ad32010-06-25 17:04:17 -040024#include <asm/traps.h>
Simon Marchi7be68282012-12-17 20:08:09 -050025#include <arch/chip.h>
Chris Metcalf867e3592010-05-28 23:09:12 -040026
27void user_enable_single_step(struct task_struct *child)
28{
29 set_tsk_thread_flag(child, TIF_SINGLESTEP);
30}
31
32void user_disable_single_step(struct task_struct *child)
33{
34 clear_tsk_thread_flag(child, TIF_SINGLESTEP);
35}
36
37/*
Chris Metcalf867e3592010-05-28 23:09:12 -040038 * Called by kernel/ptrace.c when detaching..
39 */
40void ptrace_disable(struct task_struct *child)
41{
42 clear_tsk_thread_flag(child, TIF_SINGLESTEP);
43
44 /*
45 * These two are currently unused, but will be set by arch_ptrace()
46 * and used in the syscall assembly when we do support them.
47 */
48 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
49}
50
Chris Metcalfcb67e162012-12-12 17:24:39 -050051/*
52 * Get registers from task and ready the result for userspace.
53 * Note that we localize the API issues to getregs() and putregs() at
54 * some cost in performance, e.g. we need a full pt_regs copy for
55 * PEEKUSR, and two copies for POKEUSR. But in general we expect
56 * GETREGS/PUTREGS to be the API of choice anyway.
57 */
58static char *getregs(struct task_struct *child, struct pt_regs *uregs)
59{
60 *uregs = *task_pt_regs(child);
61
62 /* Set up flags ABI bits. */
63 uregs->flags = 0;
64#ifdef CONFIG_COMPAT
65 if (task_thread_info(child)->status & TS_COMPAT)
66 uregs->flags |= PT_FLAGS_COMPAT;
67#endif
68
69 return (char *)uregs;
70}
71
72/* Put registers back to task. */
73static void putregs(struct task_struct *child, struct pt_regs *uregs)
74{
75 struct pt_regs *regs = task_pt_regs(child);
76
77 /* Don't allow overwriting the kernel-internal flags word. */
78 uregs->flags = regs->flags;
79
80 /* Only allow setting the ICS bit in the ex1 word. */
81 uregs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(uregs->ex1));
82
83 *regs = *uregs;
84}
85
Simon Marchi7be68282012-12-17 20:08:09 -050086enum tile_regset {
87 REGSET_GPR,
88};
89
90static int tile_gpr_get(struct task_struct *target,
91 const struct user_regset *regset,
92 unsigned int pos, unsigned int count,
93 void *kbuf, void __user *ubuf)
94{
95 struct pt_regs regs;
96
97 getregs(target, &regs);
98
99 return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &regs, 0,
100 sizeof(regs));
101}
102
103static int tile_gpr_set(struct task_struct *target,
104 const struct user_regset *regset,
105 unsigned int pos, unsigned int count,
106 const void *kbuf, const void __user *ubuf)
107{
108 int ret;
109 struct pt_regs regs;
110
111 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0,
112 sizeof(regs));
113 if (ret)
114 return ret;
115
116 putregs(target, &regs);
117
118 return 0;
119}
120
121static const struct user_regset tile_user_regset[] = {
122 [REGSET_GPR] = {
123 .core_note_type = NT_PRSTATUS,
124 .n = ELF_NGREG,
125 .size = sizeof(elf_greg_t),
126 .align = sizeof(elf_greg_t),
127 .get = tile_gpr_get,
128 .set = tile_gpr_set,
129 },
130};
131
132static const struct user_regset_view tile_user_regset_view = {
133 .name = CHIP_ARCH_NAME,
134 .e_machine = ELF_ARCH,
135 .ei_osabi = ELF_OSABI,
136 .regsets = tile_user_regset,
137 .n = ARRAY_SIZE(tile_user_regset),
138};
139
140const struct user_regset_view *task_user_regset_view(struct task_struct *task)
141{
142 return &tile_user_regset_view;
143}
144
Namhyung Kim9b05a692010-10-27 15:33:47 -0700145long arch_ptrace(struct task_struct *child, long request,
146 unsigned long addr, unsigned long data)
Chris Metcalf867e3592010-05-28 23:09:12 -0400147{
Chris Metcalfce7f2a32010-10-14 16:48:00 -0400148 unsigned long __user *datap = (long __user __force *)data;
Chris Metcalf867e3592010-05-28 23:09:12 -0400149 unsigned long tmp;
Chris Metcalf867e3592010-05-28 23:09:12 -0400150 long ret = -EIO;
Chris Metcalfce7f2a32010-10-14 16:48:00 -0400151 char *childreg;
Chris Metcalf1deb9c52010-10-28 15:47:06 -0400152 struct pt_regs copyregs;
Chris Metcalf867e3592010-05-28 23:09:12 -0400153
154 switch (request) {
155
156 case PTRACE_PEEKUSR: /* Read register from pt_regs. */
Namhyung Kim8c0acac2010-10-27 15:34:04 -0700157 if (addr >= PTREGS_SIZE)
Chris Metcalf867e3592010-05-28 23:09:12 -0400158 break;
Chris Metcalfcb67e162012-12-12 17:24:39 -0500159 childreg = getregs(child, &copyregs) + addr;
Chris Metcalfce7f2a32010-10-14 16:48:00 -0400160#ifdef CONFIG_COMPAT
161 if (is_compat_task()) {
162 if (addr & (sizeof(compat_long_t)-1))
163 break;
164 ret = put_user(*(compat_long_t *)childreg,
165 (compat_long_t __user *)datap);
166 } else
167#endif
168 {
169 if (addr & (sizeof(long)-1))
170 break;
171 ret = put_user(*(long *)childreg, datap);
172 }
Chris Metcalf867e3592010-05-28 23:09:12 -0400173 break;
174
175 case PTRACE_POKEUSR: /* Write register in pt_regs. */
Namhyung Kim8c0acac2010-10-27 15:34:04 -0700176 if (addr >= PTREGS_SIZE)
Chris Metcalf867e3592010-05-28 23:09:12 -0400177 break;
Chris Metcalfcb67e162012-12-12 17:24:39 -0500178 childreg = getregs(child, &copyregs) + addr;
Chris Metcalfce7f2a32010-10-14 16:48:00 -0400179#ifdef CONFIG_COMPAT
180 if (is_compat_task()) {
181 if (addr & (sizeof(compat_long_t)-1))
182 break;
183 *(compat_long_t *)childreg = data;
184 } else
185#endif
186 {
187 if (addr & (sizeof(long)-1))
188 break;
189 *(long *)childreg = data;
190 }
Chris Metcalfcb67e162012-12-12 17:24:39 -0500191 putregs(child, &copyregs);
Chris Metcalfbcd97c32010-07-02 14:17:52 -0400192 ret = 0;
Chris Metcalf867e3592010-05-28 23:09:12 -0400193 break;
194
195 case PTRACE_GETREGS: /* Get all registers from the child. */
Simon Marchi9af62542012-12-17 20:08:10 -0500196 ret = copy_regset_to_user(child, &tile_user_regset_view,
197 REGSET_GPR, 0,
198 sizeof(struct pt_regs), datap);
Chris Metcalf867e3592010-05-28 23:09:12 -0400199 break;
200
201 case PTRACE_SETREGS: /* Set all registers in the child. */
Simon Marchi9af62542012-12-17 20:08:10 -0500202 ret = copy_regset_from_user(child, &tile_user_regset_view,
203 REGSET_GPR, 0,
204 sizeof(struct pt_regs), datap);
Chris Metcalf867e3592010-05-28 23:09:12 -0400205 break;
206
207 case PTRACE_GETFPREGS: /* Get the child FPU state. */
208 case PTRACE_SETFPREGS: /* Set the child FPU state. */
209 break;
210
211 case PTRACE_SETOPTIONS:
212 /* Support TILE-specific ptrace options. */
Chris Metcalf395e0952012-12-13 11:34:45 -0500213 BUILD_BUG_ON(PTRACE_O_MASK_TILE & PTRACE_O_MASK);
Chris Metcalf867e3592010-05-28 23:09:12 -0400214 tmp = data & PTRACE_O_MASK_TILE;
215 data &= ~PTRACE_O_MASK_TILE;
216 ret = ptrace_request(child, request, addr, data);
Chris Metcalf395e0952012-12-13 11:34:45 -0500217 if (ret == 0) {
218 unsigned int flags = child->ptrace;
219 flags &= ~(PTRACE_O_MASK_TILE << PT_OPT_FLAG_SHIFT);
220 flags |= (tmp << PT_OPT_FLAG_SHIFT);
221 child->ptrace = flags;
222 }
Chris Metcalf867e3592010-05-28 23:09:12 -0400223 break;
224
225 default:
226#ifdef CONFIG_COMPAT
227 if (task_thread_info(current)->status & TS_COMPAT) {
228 ret = compat_ptrace_request(child, request,
229 addr, data);
230 break;
231 }
232#endif
233 ret = ptrace_request(child, request, addr, data);
234 break;
235 }
236
237 return ret;
238}
239
240#ifdef CONFIG_COMPAT
241/* Not used; we handle compat issues in arch_ptrace() directly. */
242long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
243 compat_ulong_t addr, compat_ulong_t data)
244{
245 BUG();
246}
247#endif
248
249void do_syscall_trace(void)
250{
251 if (!test_thread_flag(TIF_SYSCALL_TRACE))
252 return;
253
254 if (!(current->ptrace & PT_PTRACED))
255 return;
256
257 /*
258 * The 0x80 provides a way for the tracing parent to distinguish
259 * between a syscall stop and SIGTRAP delivery
260 */
261 ptrace_notify(SIGTRAP|((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0));
262
263 /*
264 * this isn't the same as continuing with a signal, but it will do
265 * for normal use. strace only continues with a signal if the
266 * stopping signal is not SIGTRAP. -brl
267 */
268 if (current->exit_code) {
269 send_sig(current->exit_code, current, 1);
270 current->exit_code = 0;
271 }
272}
273
274void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
275{
276 struct siginfo info;
277
278 memset(&info, 0, sizeof(info));
279 info.si_signo = SIGTRAP;
280 info.si_code = TRAP_BRKPT;
281 info.si_addr = (void __user *) regs->pc;
282
283 /* Send us the fakey SIGTRAP */
284 force_sig_info(SIGTRAP, &info, tsk);
285}
286
287/* Handle synthetic interrupt delivered only by the simulator. */
288void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
289{
290 send_sigtrap(current, regs, fault_num);
291}